ruths



May 25 1926.

J. K. RUTHS STEAM ACCUMULATOR PLANT AND METHOD OF OPERATING THE SAME 3 Sheets-Sheei 1 Filed June 20, 1919 May 25 1926. 1,585,790

J.K.RUTHS STEAM ACCUMULATOR PLANT AND METHOD OF OPERATING THE SAME 3 Sheets-Sheet 2 Filed June 20 1919 Hill ILIHI UUUKUUI May 25 1926. 1,585,790

, J. K. RUTHS STEAM AGCUMULATOR PLANT AND METHOD OF OPERATING THE SAME Filed June 20 1919 3 sheets-shg l F4 hwni r War 1X Patented May 25, 19

UNITED STATE JOHANNES KARL RUTHS. OF DJURSI-IOLM. S'WEDEN. ASSIGNOR TO AKTIEBOLAGET VAPORACKUMULATOR. OF STOCKHOLM, SWEDEN, A CORPORATION.

STEAM-ACCUMULATOR PLANT AND METHOD OF OPERATING THE SAME.

App1ication filed June 20. 1919, Serial No. 305,622, and in Sweden June 29, 1918.

My invention relates to steam plants equipped with steam accumulators.

Steam accumulators, as previously known. are of two clases; first, those which even out the variations in exhaust of certain intermit tently operating reciprocating steam en gines. principally steam hammers. and. ond. those which relieve boilers ot variations in steam consumption or take care of variations between steam generation and steam consumption. An accumulator ot the first class is chiefly an equalizer and has very little accumulating ability. It always discharges into a turbine operating at extremely low pressure. and has pressure variations of about six pounds and less, wherefore it cannot take care of any appreciable variations in consumption of the turbine. in the second class of accumulators large peaks ol steam consumption are taken care or and large quantities of steam are accumulated. This causes large variations in pressure in the accumulator which give rise to many problems.

Ely invention relates to plants equipped with accumulators ot the second class. wherein large variations of pressure occur. Previously to this invention it has been impossible to successfully build steam plants embodying this type of accumulator since no apparatus has been known which would contine the great pressure variations to the accuniulator so that they would not att'cct other elements of the plant, particularly the boilers, which can not stand up under such heavy variations.

Consumers receiving steam from an accumulator have been relieved of variations in the accumulator by means of a reducing; valve but this did not relieve those eleme: s which are connected ahead ot' the accumulator of variations in pressure.

I have previously, in certain cases. tlt. signed plants with a nozzle ot the La val type. inserted in the path ot stam from the generator to the acumulator, serving an entirel v dilterent purpose from the arrangements of this invention. This device ooerated so that the generator pressure did not vary as did the pressure in the accumulator. l-lovi'- ever, this arrangement has many disadvantages and in many cases causes variations of pressure in the generator of greater magnitude than it the generator and accumulator were directly connected.

My present invention aims to provide an arrangement whereby the variations of pressure occurring in a plant embodying an accumulator ot the second class as above described are confined to the accun'iulator so that the boilers are relieved or these pressure variations and can be opearted atsubstantially constant pressure, while, at the same time, an independence between the momentary steam generation and steam consumption is etl'ected and the accumulator will take care of all variations wherever they occur in the plant. thus. for the first time, making the use of such accumulators actually possible in practice in all manner of plants. no matter when or where the variations occur.

Other objects of my invention are to maintain a constant generator pressure aut0matically in a plant having a variation between steam generation and steam consumption; to relieve a plant of variations due to unequal application or heat to a generator. which are unavoidable in all plants, due to irregular composition or fuel and unavoidable variations in tiring, or where generators are heated by such variable tuels as blast furnace gases. exhaust from industrial furnaces, or e ectric current, and to relieve a plant of variations in steam consumption of consumers connected ahead of an accuimilator.

By maintaining constant boiler pressure, the arrangements of my invention give rise to a new system of operation of steam plants wherein regulation of heat supply to the boilers is effected in accordance with the state ot' charge of the accun'iulator. This method ta \ilitates accumulation in a plant since it allows a smaller accumulator than otherwise would be necessary.

The apparatus, which, I believe, best characterize my invention is the combination of a boiler, an accumulator, a passage for steam 'i'rom the boiler to the accumulator, and automatically operating pressure controlled means operating to simultaneously control said passage and maintain a constant or practically constant pressure in the boiler.

In one phase, my invention consists in the combination with one or more steam boilers, a steam conduit system connected there with, an accumulator in the system serving ing to store steam when boilers generate more steam than is converted to use, and one or more consumers in the system, or" one or more automatically operating valves regulating the flow of steam within the system and to the accumulator, said valve or valves being constructed and arranged to maintain a practically constant pressure in the boilers and various other parts of the system and to allow the process of steam generation to be unaffected by the accumulating action.

In another phase of my invention, it consists in a boiler unit, a consumer supplied therefrom at boiler pressure, an accumulator receiving steam from the boiler and connected to supply a consumer, and automatically operating pressure controlled means regulating the flow of steam from the boiler to or towards the accumulator and operating to maintain a constant pressure of steam both for the boiler and for the consumer regardless of the fact that the boiler generation or the consumption of the consumer or both may he at a varying rate and that therefore the said flow of steam may be at varying rate.

The invention consists also in the improved method involved in carrying my invention into eilect.

In the particular forms of the invention shown by way of example, the automatically operating pressure controlled means is in the form of a valve n'rechanism which I term an Over-flow valve, and it is inserted in a conduit leadingstean'i in direction toward the accumulator, the said valve being so constructed that it will increase the steam flow upon an increase of the actuating pressure above a predetermined value, and will decrease the steam flow upon a decrease of the pressure below a predetermined value, thereby operating to maintain the actuating pressure constant.

The invention will be descril ied more in detail with reference to the examples shown in the accompanying drawings. in which:

Fig. 1 is a diagrammatic view or a steam plant having my invention embodied there in in one form.

2 is a similar view of a steam plant embodying my invention in modified form.

3 is a similar view of still another modification of the invention.

Fig. 4: is a vertical sectional elevation of one form of over-flow valve.

Fig. 5 is a similar view of an over-flow valve and a reducing valve mechanically interconnected with each other.

Fig. 6 is a sin'iilasr view of two reducing valves mechanically inter-connected with each other.

Fig. 7 is a diagrammatic view of a steam plant equipped with over-flow valves, and with reducing valves of the forms shown in Figs. 4, 5 and 6.

Referring to the drawings:

In the steam plant diagrammatically shown in Fig. 1, steam is supplied by a steam generator P comprising one or more boilers through a conduit L to a steam consumer 1),. From the conduit L a conduit a leads to a steam accumulator A. In the conduit a an over-flow valve G is arranged. which valve is constructed, as will be described more in detail later on, to peianit the passage oi steam when the pressure in hunt of the valve reaches a predetermined value and, when the pressure is within an operating range above this value, to increase the steam flow through the conduit on rise ot the actuating pressure and decrease the steam flow on decrease of the actuating pressure, such actions of the valve being, in the normal operation of the plant, independent of the pressure in the accumulator. To the steam space of the accumulator A, which is partly filled with water, a conduit 6 is connected, in which a reducing valve R is inserted. This reducing valve controls the amount of steam supplied by the accumulator to the conduit L to which the conduit Z) is connected, and the valve R is of a well known construction which will maintain a practically constant pressure in the said conduit L from which. a steam consumer D is led. i -mother reducing valve R which may be of similar construction to that of valve R is inserted in the conduit system in parallel with the said over-flow valve G and allows steam to flow into the accun'iulator A only in case the latter becomes completely discharged, as will be hereinafter more fully described.

A pressure gage l d is mounted in the vicinity of the steam generator P and is connected by a pressure transmitting tube to the steam space ot accumulator A. This gage indicates the pressure in the accumulator and, as the accumulator pressure is a function of the state of charge of the accumulator. the pressure gage is a means for indicating the state of charge.

The operation of the plant above described is as follows:

The steam generated in the generator l is led through the conduit L, partly to the steam consumer D and partly through the over-flow valve G to the accumulator A, and from the accumulator the steam passes to the steam consumer D Assuming that the steam pressure in the conduit L, IS in creased. due to decreased steam consumption ot' the consumer D or to increased steam generation, the over-flow valve G will open more and will permit more steam to pass into the accumulator r Assuming on the contrary that the said steam pressure decreases, due to increased steam consumption, or to decreased steam generation, then the over-flow valve will decrease the steam tlow to the accumulator so as to maintain a practically constant pressure in the conduit L Since the over-flow valve it operates to maintain a constant pressure in the boilers .P and connected piping, the ordinary sys tem of boiler plant operation wherein the intensity of heat supply to boilers is controlled in accordance with the pressure in the boilers is not adaptable to regulation ot the intensity of heat supply in systems according to the present invention. However, by means of the pressure gage M the intensity of heat supply can readily be regulated, the supply of heat to the boilers being increased when the state of charge of the accunuilator, as indicated by pressure page M, is low, and decreased when the state of charge is high, so that reducing valve ll need not open and. on increase of pressure in conduit L blowing of safety valves need not take place.

It has been found in practice that the the room force learns to regulate the tires just. as easily by watching the pressure gage indicating the variable accumulator pressure as by watching a gage indicating boiler pressure and the tires may be driven at a uni form intensity for the greater part of the. time and need not be regulated as often as is the case without an accumulator, a matter which has been proved by experiments to give higher combustion efiiciency.

Should the accumulator become completely discharged, as might occur in exceptional cases. additional steam must be taken tlOiTl the generator independently oi the control of the steam by the over-flow valve G This object is accomplished by the reduction valve R the construction of which is such that it will open and allow steam to pass through it when the pressure in the accumulator, due to the ('lischarn'e Of the same. decreases beyond a certain value. In these circumstances. the pressure in the coin duit L will fall below the pressure required to open the over-Flow valve. and this valve will therefore remain closed and the whole quantity of steam will flow through the reducing valve to the accumulator and thence to the consumer. In this way the consumer will be supplied with the necessary quantity ot steam independently of the control of the steam by the over-flow valve. To increase the generation of steam under thee conditions, in order to reestablish the normal working conditions of the plant. greater heat must he applied to the generator, the att ndant being apprised the neccssitv of doine so hv observing the pressure indicator which is coenectcd with the accumulator.

Fig. 2 shows the same arrangement of the ovcr tlow valve in a steam plant in which ihe steam accumulator is connected in parallel with a conduit connecting the overflow valve with the consumer, non-rcturn valves T, and v2. being inserted in the connections between the accumulator and said conduit.

Fig. 3 shows a plant comprising a main conduit L, connected to the generator, and several secondary steam conduit L L and L carrying each a ditl'ercnt steam pressure, and to which conduits the steam consumers l3 1),. 1)., and l), re connected. Between these conduits, the over-flow valves G Gr and (in and the reducing: valves R R and v are arranged as shown, and in the coniit L. the reducing valve It is inserted. Ehipposinp now for instance, that the pres sure in the conduit It: increases above a predetermined value. the over-tlow valve G will open and admit the surplus of steam into the conduit I From this conduit a certain amount ot steam not being consumed by consumer 1),. will pass through the over-How valve G in direction towards the accumulator A. The accumulator will he chm-51rd it the said quantity of steam passing through the over-tlow valve exceeds the amount ot steam required at the same moment by the steam consumer D and. on the contrary, the accumulator will discharge in case the steam flow through the reducing; valve ll, exceeds the steam flow through the over-flow valve G lie it supposed as another example, that the pressure in the conduit L decreases below a predetermined value. Then the over-fiow valve G will decrease the steam flow to the conduit i In exceptional cases it may happen, that this valve G will close completely. Then, with further dec easing pres sure in the conduit L the reducing valve l will open and admit steam from the conduit ll, into the conduit L Due to the cut-oil ot the steam supply through the over flow valve (l.,,,, the pressure in the conduit will also decrease and open the reducing valve I? so as to admit steam from the conduit I to the conduit L Before the reducing valve ll, begins to open, the overtlov: valve (i will he closed so that no steam i-t su nilicd to the accumulator. In such a cane. thcre'lore. the consumer D is fed with storm 'lrom the accumulator only. The reduciiu); valve 11,. controls this steam flow rom the accumulator to the consumer D, so as to maintain a practica lv constant pressure in the conduit ll Should it happen, that the accumulator be completely discharged and fails to supply a sutlicient quantity cl steam to the conduit I in spite of the reducina: valve ll. being completely pen. then. noon decrease of the pressure in a ccnuint L, below a prciiletermined value,

the reducing valve ll, will be opened so as to admit the desired quantity of steam to the conduit L From the above, it will be evident, that with such an arrangement of regulating means together with an accumulator, the latter will take care of all variations wherever they occur in the plant, and that the pressures in the conduits L L,. L, and L will be maintained at respectively different, and practically constant values.

In Fig. l: the detailed construction of an over-flow valve of one term suitable for carrying my invention into effect is shown. In this figure it will be seen that the valve comprises a ca.'ng H provided at opposite sides with ports I and K, the port I being connected with the conduit L, of Fig. 1 and the port K being connected with the conduit a of Fig. 1. Within the casing is a chamber L connecting with the port K, which chamber is termed with aligned ports Z- and Z, which are controlled by a cut-off valve member G comprising a plurality ot discs carried by an operating stem N. This stem is connected with means tor operatinethe valve member, which means consists oi: a bellows T5,, the interior of which is in communication with the interior of the casing. and a spring F which bears against the bellows and exerts its force in opposition to the expansive action of the bellows. From this construction it will be understood that the spring F being set to resist a predetermined pressure, the bellows will er:- paud and will move the valve member and begin to open the )orts Z and 1,, when the pressure of the stean'l entering the casing through conduit- L, overcomes the resistance of the spring. so that steam will flow through the valve and enter the conduit to and thence pass into the accumulator, it being understood that the increase of pressure above that necessary to start the opening movement will act to open the valve to a greater extent, until at a still greater predetermined pressure, thevalve will be fully opened. It will thus be understood that it any tuedetermined clue is selected, lying within the perating range between the predetermined value for complete closure of the valve and the predetermined value for full opening of the valve, that an increase of the actuating pressure above said any predetermined value wnl result in an increase of steam flow through the valve and a decrease of pressure below said any predetermined value will result in decrease of flow of steam through the valve. The over-flow valve is a regulating valve in normal operation.

The valve meml'ier G is balanced as shown, in respect to the action of the steam pressure thereon, so that the opening and throttling mo ements of the valve member under the influence of the pressures in the conduit in front of the valve acting on the bellows are independent of the pressures acting on the valve member itself. In these circumstances the movements of the valve member nuclei the influence of the pressure acting in front or the valve are independent 01 the pressure, the accumulator pressure in l and 2, acting behind the valve.

From the description of Fig. 3 it will be understood that with decreasing pressure, tor instance in the conduit T1,, the over-flow valve G will close, and when completely closed and with further decreasing pressure, the reducing valve R will open. These two valves should therefore be so relatively adjusted, that with a certain pres sure value in the conduit L, both valves will be closed; and should the pressure rise above said value, then the over-flow valve will open, and the reducing valve will remain closed: and should on the other hand, the pressure decrease below said value, the reducing valve will open and the over-flow valve will remain closed.

These relative actions of the two valves mav he obtained by mechanically inter-connecting them. as shown for instance in Figs. and 7. The reducing valve member and the overflow valve member 21 .in Fig. correspond to the respective valves R and (i of Fig. 3. From the d'awing it wil be seen that both valves are arranged in a common casing H having near one end aport connected with the conduit ll of Figs. 3 and 7, and having near its opposite end a port connected to conduit L, of said ligures. A third port is provided in the casing which is connected to the conduit L, leading to the accumulator as shown in dig. 7. A chamber L extends into the casing from the port conn'nunicating with the conduit L which chamber is provided with aligned ports 7 and 1,; and a second chau'il'wr lit, extends into the casing from the port leading to the accumulator, which chamber is provided with aligned ports Z. am 7,. The two valve members 20 and 21, similar to the member G of Fig. 4, are providcd to control the ports in the respective chambers, and these members slide on a f-lelll Fl guided in the casing. A springj of relatively small force-encircles the stem between the two *alve members and tends to hold them vieldiugly in positions to close the r respective ports. The stem is connected, in a manner similar to that shown in Fig. l. to a bellows ll, which is acted on bv a spring F. The stem has fixed to it two collars l3, and R, in position, to en- !i'agre the two valve members, the arrangement being such that when the stem is. moved endwise in one direction, one of the collars will engage and open one of the valve members while not disturbing the other, and when the stem is moved endwise in the opposite direction, the other valve member will be opened without disturbing the first.

From this description it will be understood that in the operation of the inter-connected reducing valve and the over-flow valve, it the pressure in conduit L rises above a predetermined value, corresponding to the force of springs F and f, the bellows will be expanded and the valve stem will be moved upwardly in Fig. 5, whereby the lower valve member 21 will be opened and will admit steam from conduit to conduit L leading to the accumulator. In this action the upper valve member 20 will be held in closed position by the spring f. On

the other hand, it the pressure in conduit L falls below a predetermined'value, spring F will contract the bellows and will move the stem downwardly, thereby opening the upper valve member 20 and admitting steam from conduit L into the valve casing and thence to conduit L in which action the lower valve member will be held closed by the spring 7.

From the description of Fig. 8 it will be further understood that the reducing valve B will open only when the reducing valve R is completely open, the reducing R being closed when the reducing valve R is only partiall opened. This function nay be obtained by mechanically inter onnecting the two reducing valves as .hown for instance in Fig. (5. Here it will be seen that a reducing valve member 30 corresponding to the reducing valve R in Fig. 3 is arranged in a main valve casing E while another reducing valve member 31, corresponding to the reducing valve R of Fig. 3 is arranged in a secondary valve casing forming an extension of the first. The main casing is provided with oppositely disposed ports con nected respectively with conduit L and conduit L the first mentioned conduit being connected with a chamber H extending into the casing and provided with aligned ports opening into the interior of the casing. The ports of the chamber H are controlled by the valve member 30 which is carried by a valve stem S movably guided in the cars ing. At its lower end the stem is connected with a bellows B subject to the pressure in the casing, which bellows is acted on by a spring F Atits opposite end the stem is connected with an open ended cylindrical slide constituting the valve member 31 movable within a cylindrical shell U having ports 0 communicating with a port in the secondary casing and connected with the conduit L The relation of the parts described is such that when the valve member 30 is partially open, the cylindrical slide will cover the ports O in the shell U. and only when the valve member 30 is fully open,

valve will the ports 0 begin to be uncovered and communication then established between the conduits L and L Fig. 7 shows a plant of the same general arrangement as that shown in Fig. 3. In Fig. 7 however the plant is shown as being equipped with the different forms of valve construct-ions shown specifically in Figs. 4, 5 and 6; G designating the over-flow valve of the form of Fig. a; G +R and G d-R designating the inter-connected over-flow and reducing valve constructions of Fig. 5; and R i-R designating the inter-connected reducing valves as shown in Fig. 6.

From the foregoing description of my invention, it will be understood that in the practice of the same, the supply of surplus steam to the accumulator arising either from increased steam generation or decreased steam consumption, is automatically regulated in accordance with the variations of pressure in the plant, and independently of the accumulator pressure; and it is manifest that while the mechanisms illustrated and described herein are suitable for carrying my improved method of steam supply into effect, the said method is not dependent for its practice on such apparatus and may be carried out by the use of apparatus of other forms.

By my invention as described above, many valuable advantages are secured, the most important of which will be briefly mentioned.

As all variations in steam generation and steam consumption are taken care of by the accumulator, modern steam generators with very small water space and with high efticiency may be employed. Further, owing to the constant generator pressure which is obtained, and the fact that forced firing ot the generator is avoided, the generators will have longer life, and will not be subjected to injurious strains which would tend to cause deterioration. As the steam generation need only be such as to correspond to the average consumption of steam, generators of minimum size may be employed, thereby securing a maximum of economy in the operation of the plant.

Further, owing to the capability of the accumulator to deliver a large quantity of steam in a very short time, the capacity of the plant in the production of goods will be increased; and as the steam pressures in all of the conduits leading to the steam consumers are maintained at constant values, a more uniform and superior quality of goods may be secured.

It appears from the above description that the accumulator may be made so large that it will permit the boiler to generate continuously the average consumption at all times in which case no regulation of tires would appear to be necessary except for unusual occurrences. However, in most plants, it is preferable to operate along a curve of varying average consumptions, that is, a curve of slowly varying steam generation or one having a given value for some time and then changing slowly to another given value for another period since, by this means, a smaller accumulator is possible and the complete advantages ot the accumulator are nevertheless obtained. In the second case my new method of heat control is of the greatest importance.

I prefer to use this method in all accumulator installations and find that the use ot the means for gaging the state of charge of the accumulator and the regulation oi boilers thereby is actually indispensable in all plants including accumulators as herein described.

Having thus described my invention, what I claim is:

1. A. boiler, an accumulator, a passage for steam from said boiler to said accumulator, and an automatic valve operating to simultaneously maintain a constant pressure in said boiler and control flow of steam through said passage.

2. A source of steam, a consumer supplied therefrom, an accumulator, a consumer supplied therefrom, a passage for steam from said source to said accumulator and an over-flow valve controlling; said passage.

8. A steam plant comprising, in combination, a steam generator, a steam conduit system connected therewith, a steam accumulator connected in said system, means in said system to consume steam, a passage for steam in said system from said generator to said accumulator, and automatically operating movable means controlling said passage independently ot the pressure in the accumulator.

4. The method of operating a steam plant which comprises generating steam at a ditterent rate than the rate of consumption, conductingthe surplus of generated. steam over the momentary consumption to an ac cumulator and accumulating the same for use when the consumption exceeds the generation, controlling flow of steam to the accumulator and in the system so that the gen erator pressure is maintained constant while variations are permitted inthe accumulator, indicating the state of charge of the accumulator and controlling the supply oi heat to the generator in accordance with the state of charge of the accumulator.

5. A steam plant comprising, in combination, a steam boiler, a steam conduit system connected therewith, a steam accumulator connected in said system, means in said system to consume steam, a passage for steam in said system from said boiler to said. accumulator, automatic means controlling said east/e0,

passage independently of accumulator pres sure and operating to maintain constant boiler pressure and means to indicate the state of charge of the accumulator and arranged to permit regulation of heat to the boiler in accordance with said state of charge.

6. steam plant comprising, in combina tion, a steam boiler, a steam conduit system connected therewith, a steam accumulator connected in said system, means in said system to consume steam, a passage for steam in said system from said boiler to said acciunulator, automatic means controlling said passage independently of accumulator pressure and operating to maintain constant boiler pressure, and a pressure gage mounted in the vicinity of said boiler and connected with the accumulator to indicate the pressure in the accumulator so that the supply of fuel to the boiler can be regulated in accordance with the state of charge of the accumulator.

7. A steam plant comprising, in combination, a steam boiler unit, a steam conduitsystem connected therewith, means in said system to consume steam, a steam accumulator in said system having a water space and a steam space and serving to regenerate steam, a passage for steam from said boiler unit to the water space oi? said accumulator, automatically operating movable means in said system controlling said passage independently 0t accumulator pressure and so that the boiler pressure is maintained con stant, said accumulator being of suiiicient capacity so that the boiler unit is made independent of steam demand and the arrangement being such that pressure variations are confined to the accumulator.

8. A source of steam, a consumer supplied therefrom at the pressure of the source, an accumulator having a steam space and a water space and serving to regenerate steam, a consumer supplied with steam from the accumulator, said accun'nilator being adapted to vary in pressure between the pressure of the second consumer and the source, a pas sage for steam from the source to the water space ot the accumulator and an over-flow valve controlling said passage in responseto pressure in the source and ')6l1tl11g to maintain a constant presssure in the source and to maintain a constant pressure of steam for the first mentioned consumer.

9. In a steam plant the combination with a steam generator, a steam conduit system connected therewith, a steam accumulator connected in said system, and a steam consinner supplied by the said accumulator, ot a valve member inserted in a conduit leading steam in direction toward the accuunilator, and means responsive to the generator pres sure to operate the said valve member to increase the steam flow throughthe said conduit upon an increase of the said pressure above a predetermined value, while decreasing the steam fiow upon a decrease of the said pressure below a predetermined value.

10. In a steam plant, the con'ibination with a steam generator, a steam conduit system connected therewith, a steam accumulator connected in said system, said conduit vstem comprising a series of conduits, each carrying a lower pressure than the pressure in the preceding conduit, a second series of conduits connecting the conduits of said first mentioned series of conduits, said second series of conduits leading steam in direction toward said accumulator, a pluralitv oi overflow valve members inserted between conduits of said first mentioned series of conduits, one in each of the conduits ot the said second series of conduits, means responsive to the respective pressures in said connecting conduits in front of said valve members to operate each of said over-flow valve mem bers to increase the steam flow through its conduit upon an increase of said pressure above a predetermined value. while decreasing the steam flow upon a decrease of said pressure below a predetermined value, and steam consumers supplied from the conduits ot' the first mentioned series of conduits.

11. In a steam plant. the combination ot a steam generator. a steam conduit system connected therewith, said conduit system comprising a i )luralit of conduits containing steam of diti'erent pressures, an accumulator connected to one of said conduits. a connecting conduit between one of the said conduits and another conduit of different pressure, said connecting conduit leading steam in direction toward said accumulator, an overflow valve member in said connecting conduit. means responsive to the pressure in said connecting conduit in front oi said valve member to operate the said valve member to increase the steam flow through the connecting conduit upon an increase of said pressure above a predetermined value. while decreasing the steam flow upon a. decrease of the said pressure below a predetermined value and steam consumers connected to the conduits of different pressures.

12. In a steam plant including a steam generator, a steam conduit system connected therewith, an accumulator in said steam conduit system and a plurality of consumers connected in said system, the. combination with a high pressure conduit ot' the said system and a low pressure conduit of the said system. of means responsive to the pressure in said high pressure conduit to pass steam to said low pressure conduit upon an increase at pressure in said high pressure conduit above a predetermined value and means responsive to the pressure in said low pressure conduit to pass steam from said high pressure conduit to said low pressure conduit upon a decrease of pressure in said low pressure conduit below a predetermined value.

13. A. steam plant as specified in claim 11 provided with second means operated by the pressure behind the said over-flow valve member and adapted to admit steam in direction toward said accumulator upon a decrease ot' the last said pressure below a predetermined value.

14. In a steam plant, the combination with a steam generator, a steam conduit system connected therewith, a steam accumulator connected in said system, a consumer supplied by the said accumulator, a conduit leading steam in direction toward said accumulator, an over-flow valve member inserted in said conduit, means responsive to the pressure in said conduit in front of said valve member to operate the same to increase the steam flow through the conduit upon an in crease of said pressure above a predetermined value while decreasing the steam fiow upon a decrease of the said pressure below a predetermined value and a reducing valve member arranged in parallel with the said over-flow valve member, and means responsive to the pressure in the conduit behind said over-fiow valve memher to open the said reducing valve member upon decrease of pressure in the conduit behind said over-flow valve member below a predetermined value,

A steam plant comprising, in combination, a steam generator. a steam conduit system connected therewith, a low pressure conduit in said system, an accumulator connected to said low pressure conduit. a con sinner connected to said low pressure conduit, a conduit oi higher pressure in said system, a consumer connected to said eonduit of higher pressure, means responsive to the pressure in said conduit of higher pressure to pass steam from said conduit oi higher pressure to said low pressure cola 'duit when said pressure is above a predetermined value and means responsive to pressure in said low pressure conduit to pass steam from said conduit of higher pressure to said low n'essurc conduit when said accumulator is discharged;

16. A steam plant as specified in claim 10, in combination therewith, a reducing valve member arranged in parallel with iachoverilow valve member and means provided for each reducing valve member, responsive to the pressure in the conduit behind said reducing valve member to open the same upon a decrease of the last said pressure below a preiiletermined value.

17. In a steam plant, the combination with a steam generator, a steam conduit system connected therewith, a steam accumulator connected in said system, of a conduit leading steam toward said accumulator, an overflow valve member inserted in said conduit, means responsive to the pressure in said conduit in front of said valve member to operate the une to increase the steam liow through the said conduit upon an increase oi the said pressure above a predetermined value while decreasing the steam :[iow upon a decrease of the said pressure below a predetermined value, a conduit leax'ling;- steam from said accumulator, a consumer connected to said lz'rst-mentioned conduit, a reducing valve member inserted in this lastmentioned conduit, means responsive to the pressure in the said last-mentioned conduit beyond the reducing valve member to open said reducing valve member upon a decrease of the last said pressure below a predetermined value While decreasing the steam flow upon an increase of the last said pressure above a predetermined value.

18. In a steam plant, the combination with a steam generator, a steam conduit system connected therewith, a steam accumulator connected in said system, of a conduit leading; steam toward said accumulater, an over-flow valve member inserted. in said conduit, means responsive to the pressure in said conduit in trout of said valve member to operate the same to incre: c the steam flow through the said cond it upon an increase of the said pressure above a predetermined value while decreasing: the steam flow upon a decrease of the said pressure below a predetermined value, a conduit leading steam from said accumulator, a consumer connected to said lttStl[1Elti()llf(l conduit, a reducing valve member inserted in this last-mentioned conduit, means re sonsive to the pressure in said last-mentn'med conduit beyond the reducing valve member to open said reducing valve member upon a decrease of the lastsaid pressure below a predetermined value while decreasin the steam flow upon an increase of th l2 said pressure above a predetermined value, and a second steam consumer supplied from the conduit in front of the overflow valve member.

19. In a steam plant, the combination with a steam generator, a steam conduit tem connected therewith and a steam accumulator connected in said system, of a conduit leading steam toward said accumulator, said conduit being; supplied with steam trom said generator, a consumer supplied by said accumulator, a valve mechanism inserted in said conduit responsive to the prcssiu-e in said conduit in front of the same and operating to maintain the said pressure constant, a second conduit to supply steam to the first mentioned conduit, and a reducing); valve mechanism in the second conduit interconnccted with the first mentioned mechanism.

20. In a steam plant, the combination with a steam generator, a steam conduit sysconnected therewith, a steam accumulater com'iected in said system, of a conduit ltltlllig steam toward said accumulator, a vaive member inserted in said conduit, means responsive to the pressure in said conduit in front of said valve member to operate the same to maintain said pressure constant, a conduit leading steam from said accumulator, a consumer connected to said last-mentioned conduit, a reducing valve member inserted in this last-mentioned condt't, means responsive to the pressure in said has entioned conduit beyond the reducing valve member upon a decrease of the last said. pressure below a predetermined value while decreasing the steam flow upon an increase of the last said pressure above a predetermined. value, a second reducing valve member connected in parallel with the first mentioned valve member, said second reducing valve member being interconnected with said first reducing valve member and means to open the second reducing valve member only when said tirst reducing,- valve member con'ipletely open.

in a steam plant, the combination vlth a steam generator, asteam conduit system connected therewitlii, a steam accumula tor t, "ected in said system, of a conduit loading steam toward said accumulator, an over-how valve member inserted in said conduit, means responsive to the pressure in said conduit in front 01" said valve member to operate the same to increase the steam flow through the said conduit upon an increase of the said pressure above a predetermined value while decreasing the steam tiow upon a decrease of the said pressure below a predetermined value, a conduit leading steam from said accumulator, a consumer connected to said last-mentioned conduit, a reducing valve member inserted in this last-mentioned conduit, means responsive to the pressure in said last-mentioned conduit beyond the reducing valve member to open said reducing valve member upon a decrease oi the last said pressure below a predetermined value while decreasing the steam. liow upon an increase of the last said pressure above a predetermined value, a second reducing; valve member connected in paralle. with the Said overflow valve member, sziid. second reducing valve member being mechanically interconnected with said first reducing valve member, means to open the second reducing valve member when said first reducing; valve memlber is completely open, and a steam consumer supplied from the conduit in front of said over-flow valve meu'iber.

in a steam plant, the combination of a steam generator, a steam consumer, a conduit connecting the generator with the conalve member to open said reducing the conduit upon an sumer, an over-flow valve member inserted in the said conduit, means for operating the same to increase the steam flow through ncrease of the pi", sure in the conduit in nt oi the over-tlow valve member, while decreasing the steam llmv upon a decrease ct pressure. a steam conduit connected in parallel with the lirst mentioned conduit, steam accumulator connected in the second mentioned conduit, and non-return in the last mentioned conduit.

A source of steam, means to consume steam, means to conduct steam from the source to the consuming means, an accumulator, means to conduct steam from the accumulator to the consuming means, a passage for steam from said source to said accumulator and an over-[low valve controlling said passage.

2st. A steam plant comprising, in combination, a steam generator, a steam conduit system connected therewith, a steam accumulator connected in said system, a steam consumer with variable steam consumption supplied directly from the generator, a steam consumer supplied with steam t'rom the accumulator, and automatically operated movable means adapted to control the passage of the surplus generated steam above the momentary consumption and pass this surplus steam to the accumulator independently of the pressure therein.

25. A. steam plant comprising, in combination, a steam generator, an accumulator, a consumer, said accumulator and consumer being connected in parallel to said generator to receive steam therefrom, a steam consumer supplied with steam from the said accumulator, pressure actuated means adapted to control the flow oi surplus steam to the accumulator, said means being inactive under a given value of the actuating pressure and adapted to become active and to be operated to control the steam flow to the accumulator when said pressure value is exceeded.

In a steam plant, the combination with a steam generator, a steam conduit system connected therewith, a. steam accumulator connected in said system, and a steam consumer supplied by the said accumulator, ot' a balanced overfiow valve inserted in a conduit leading steam in direction toward the accumulator, and a steam consumer receiving steam in front of said valve.

27. In a steam plant, in combination, a boiler, an accumulator, a passage for steam from said boiler to said accumulator, a balanced valve in said passage comprising a reciprocatin stem, a plurality of discs attached thereto, each controlling an opening said valve, pressure operated means to move said stem, to increase the opening through the valve upon increase of pressure valves in front of the same, and a consumer supplied by the accumulator.

In a steam plant, the combination with a steam generator. a steam conduit system connected therewith, a steam accumuator ciumected in said system and a steam er supplied by the sa d accumulator, r it la ding steam in direction toward said accumulator. a branch connection leading from said conduit, a second consumer connected to said branch connection, an overtic-w valve member inserted in the said conduit beyond the said branch connection and means adapted to operate the said valve member to increase the steam flow through the said conduit upon an increase of the pressure in the said conduit in front of the said valve member above a predetermined value, while decreasing the steam tlow upon a decrease of the said pressure below a predetermined value.

29. In a steam plant, the combination with a steam generator, a steam conduit system connected therewith, a steam accumulator connected in said system, and a steam consumer supplied by the said accumulator, of an overlow valve inserted in a conduit leading steam toward the accumulator, said overflow valve comprising means adapted to opcrate the valve to increase the steam supply through the said conduit upon an increase of the pressure in the said conduit in front of the valve above a predetermined value, while decreasing the steam flow upon a decrease of the said pressure below a predetermined value, and a steam consumer supplied trom the said conduit in front of the said over-flow valve.

30. In combination, a waste heat boiler. a consumer, an accumulator, a passage for steam from the accumulator to the eonsinner, a passage for steam from the waste heat boiler to the accumulator and an overllow valve controlling the last-named passage.

31. In combination, a boiler having a variable supply of fuel, a consumer. an accumulator, a passage for steam from the boiler to the accumulator, an over-flow valve controlling said passage and means to conduct steam from said accumulator to said consumer.

82. In combination, a waste heat boiler, a steam conduit system connected to receive steam therefrom, a steam accumulator connected in said conduit system, a consumer supplied by said accumulator, a valve member inserted in a conduitof said system leading steam in direction toward the accumulator, means adapted to operate said valve member to increase the steam flow through the same upon an increase of pressure above a predetermined value and decrease the steam flow upon a decrease of pressure below a predetermined value.

(T Q D tug etezun whlch. comprlses PlOClIlG n9 stezun 1 $110 method of pt'otlucin uucl tlltp nsat 2 cli 't'ercnt re e than the rate of consumption. eccun'ruhtth steam when the eo1nu1nption is less then the stezuu generation, reguletting the amount 0'? stezun accumulated so that the pressure ot the nut-ed steam is maintained constant and withdrawing steam to use from the accumulator when the censunlption exceeds the n'romentzuv'y stezun genera-Lieu.

34-. That ln'xprovement in the art of c0ntrolling steam plants employing steam aceul'nulators which c0. sluts in automatica ly regulating the stennl flow to the accumulator in eccertnnce with the generator pressure,

end i1r.tle} encle1'1tl of the accumulator pres-- sure so that the generator pressure is main tanned constant. A

That improvement in the art of generating and dispensing steam in .a steam plant equipped with :1 steam generator, steam consumers, and a steam accumulator which consists in euton'urtically regulating the flow of steam to and from the accumulutrr, so to maintain a constant steam pressure in the generator and for the coneurners and confining variations of pressure in the plant to the accumulator.

In testimony whereof I nth): my signature.

JOHANNES KARL RUTHS. 

